Packing case for substrates of flat display device

ABSTRACT

An exemplary packing case ( 20 ) includes a main body ( 21 ) and a plurality of protrusions ( 213 ). The main body includes four side walls configured for receiving substrates. The protrusions are formed at inner sides of two opposite side walls of the main body, respectively. The protrusions are separately parallel to each other. Each of the protrusions has a wedge shape and is perpendicular to the two opposite side walls. Each two adjacent protrusions define a groove ( 215 ) therebetween. The groove includes a first portion and a second portion. The first portion is adjacent to the corresponding side wall. A width of the second portion increases along with increasing of a distance far away from the corresponding side wall.

FIELD OF THE INVENTION

The present invention relates to packing cases, and more particularly toa packing case that can be used to hold or transport flat, thin objectssuch as substrates of flat display devices.

GENERAL BACKGROUND

Because the liquid crystal display has the advantages of portability,low power consumption, and low radiation, the liquid crystal display isconsidered by many to have the potential to completely replace cathoderay tube displays. Typically, a liquid crystal display includes a liquidcrystal panel, which has a thin film transistor (TFT) substrate and acolor filter substrate. In mass production of the liquid crystaldisplay, the TFT and color filter substrates are manufactured indifferent sections of a factory. Then the TFT and color filtersubstrates need to be transported to the same section of the factory forassembly. Packing cases are usually needed for holding and transportingthe TFT and color filter substrates.

A typical packing case generally includes a main body and a cover. Themain body together with the cover forms a closed space for receiving theTFT and color filter substrates therein. The main component of the TFTand color filter substrates is glass, therefore the TFT and color filtersubstrates are fragile and easily damaged if subjected to externalimpact. In order to prevent the TFT and color filter substrates frombeing damaged, a partition layer used as a shock absorber is providedbetween each two adjacent TFT substrates or color filter substrates inthe packing case.

Each TFT substrate or color filter substrate generally includeselectronic components such as TFTs formed at a display area of thesubstrate, and auxiliary circuits such as an electrostatic dischargecircuit formed at peripheral sides of the display area. However, theelectronic components and auxiliary circuits are liable to be damaged byfriction between the substrate and either or both of the partitionlayers when the substrate is inserted into or taken out of the packingcase.

What is needed, therefore, is a packing case that can overcome theabove-described deficiencies.

SUMMARY

A packing case includes a main body having four side walls, and aplurality of protrusions formed at inner sides of two opposite of theside walls. At each of the opposite side walls, the protrusions areseparate from each other and parallel to each other. Each of theprotrusions has a wedge shape and is perpendicular to the side walls.Each two adjacent protrusions define a groove therebetween. The grooveincludes a first portion and a second portion. The first portion isadjacent to the side wall, and a width of the second portion increaseswith increasing distance away from the side wall.

A packing case includes a main body having four side walls, and aplurality of protrusions formed at inner sides of two opposite of theside walls of the main body. At each of the opposite side walls, theprotrusions are separate from each other and parallel to each other.Each of the protrusions has a wedge shape and is perpendicular to theside wall. Each two adjacent protrusions define a groove therebetween.The groove includes a first portion and a second portion. The firstportion is adjacent to the side wall and has a uniform width, and thesecond portion flares from the first portion such that a width of thesecond portion adjacent to the first portion is the same as the width ofthe first portion and a width of the second portion farthest from thefirst portion is greater than the width of the first portion.

Other novel features and advantages will become more apparent from thefollowing detailed description when taken in conjunction with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded, isometric view of a packing case according to anexemplary embodiment of the present invention, and also showing twosubstrates.

FIG. 2 is an enlarged view of a circled portion II of FIG. 1.

FIG. 3 is a top plan view of a main body of the packing case of FIG. 1.

FIG. 4 is an isometric view of the main body of the packing case of FIG.1 holding the two substrates therein.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Reference will now be made to the drawings to describe preferred andexemplary embodiments in detail.

FIG. 1 is an exploded, isometric view showing a packing case accordingto an exemplary embodiment of the present invention. The packing case 20includes a cover 21 and a main body 25. The cover 21 coupled with themain body 25 cooperatively define a closed space for holding ortransporting flat, thin objects, which may for example be substrates 40of flat display devices. The flat display devices may for example beliquid crystal displays or plasma displays. The substrates 40 may forexample be TFT substrates and color filter substrates of liquid crystaldisplay panels, or glass substrates of plasma display panels.

The packing case 20 may be made of foam resin. The resin may be highdensity polyethylene, high density polypropylene, low densitypolyethylene, low density polypropylene, or another polyolefin material.The foam resin is fabricated by expansion foaming, whereby a size of thefinished foam resin is about 3 to 30 times its original size. Theforming process may be performed by way of heating up the foam resinwith a mold. The process may also be a low pressure foaming process.Various portions of the packing case 20 typically have a thickness inthe range from 15 mm to 100 mm.

The main body 25 includes a bottom 212, a first side wall 216, a secondside wall 217, a third side wall 218 opposite to the first side wall216, and a fourth side wall 219 opposite to the second side wall 217.The first, second, third, and fourth side walls 216, 217, 218, 219 arearranged end to end, and perpendicularly extend from the bottom 212.Thereby, the first, second, third, and fourth side walls 216, 217, 218,219 together with the bottom 212 define a space for receiving thesubstrates 40. At a top of each of the first, second, third, and fourthside walls 216, 217, 218, 219, an inner portion of the first, second,third, and fourth side walls 216, 217, 218, 219 protrudes up higher thanan outer portion of the first, second, third, and fourth side wall 216,217, 218, 219. Thereby, an inner peripheral protruding rim (not labeled)is formed at the top of the main body 25, with an outer peripheral ledgeof the top of the main body 25 surrounding a bottom of the innerperipheral protruding rim. The cover 21 can thereby be fittingly engagedon the top of the main body 25, with a bottom of the cover abutting theledge of the main body 25, and an inner peripheral wall of the coverabutting the inner peripheral protruding rim of the main body 25.

Each of the first and third side walls 216, 218 includes a plurality offirst protrusions 213 formed at an inner surface thereof. At each of thefirst and third side walls 216, 218, the first protrusions 213 areparallel to each other, separate from each other, and evenly spacedapart. All the first protrusions 213 of the first and third side walls216, 218 have substantially the same configuration. Each of the firstprotrusions 213 has a wedge shape, and perpendicularly extends from theinner surface of the first or third side wall 216, 218. The firstprotrusions 213 of the first side wall 216 are symmetrically oppositethe first protrusions 213 of the third side wall 218. Each two adjacentfirst protrusions 213 together with a corresponding portion of the firstside wall 216 or third side wall 218 cooperatively define a first groove215. The first grooves 215 are oriented perpendicular to the bottom 212of the main body 25. The first grooves 215 of the first side wall 216are symmetrically opposite the first grooves 215 of the third side wall218.

Also referring to FIG. 2, this is an enlarged view of a circled portionII of FIG. 1. Each of the first protrusions 213 includes a first surface2131, a second surface 2133 parallel to the first surface 2131, and athird surface 2135. The first surface 2131 and the second surface 2133are each perpendicular to the third side wall 218. The first surface2131 has an area larger than an area of the second surface 2133. Thethird surface 2135 extends from an end of the second surface 2133 in adirection oblique to the third side wall 218. The second surface 2133together with a corresponding portion of the first surface 2131 of anadjacent protrusion 213 cooperatively define a first portion (notlabeled) of the first groove 215 therebetween. The third surface 2135together with another corresponding portion of the first surface 2131 ofthe adjacent protrusion 213 cooperatively define a second portion (notlabeled) of the first groove 215 therebetween.

The first portion of the first groove 215 has a width approximatelyequal to a thickness of the substrate 40. A width of the second portionof the first groove 215 increases with increasing distance away from thethird side wall 218.

Also referring to FIG. 3, this is a top plan view of the main body 25.The bottom 212 includes a plurality of second protrusions 251. All thesecond protrusions 251 have the same configuration. Each secondprotrusion 251 is strip-shaped, and extends perpendicularly up from aninner surface (not labeled) of the bottom 212. The second protrusions251 are arranged in two lines, which lines are parallel to each otherand parallel to the first and third side walls 216, 218. The two linesof second protrusions 251 are at opposite sides of a central axis (notshown) of the bottom 212, and spaced a same distance from the centralaxis. In each line, the second protrusions 251 are parallel to eachother, separate from each other, and evenly spaced apart. Thus each twoadjacent second protrusions 251 together with a corresponding portion ofthe bottom 212 cooperatively define a second groove 253. The secondgrooves 253 at the bottom 212 are aligned with the first grooves 215 atboth the first and the third side walls 216, 218. Accordingly, a secondgroove 253 in one of the lines, the aligned second groove 253 in theother line, and the aligned first grooves 215 of the first and thirdside walls 216, 218 cooperatively define a groove unit (not labeled) forreceiving a substrate 40.

When a substrate 40 is received in the packing case 20, the substrate 40is inserted into a groove unit. A side of the substrate 40 that haselectronic components and auxiliary circuits contacts the secondsurfaces 2133 of the first protrusions 215. The other side of thesubstrate 40 contacts the first surfaces 2131 of the first protrusions215. Thereby, three edges of the substrate 40 corresponding to the firstside wall 216, the third side wall 218, and the bottom 212 are receivedin a groove unit, as shown in FIG. 4.

As detailed above, the first protrusions 213 are provided at the firstand third side walls 216, 218, and the second grooves 253 are providedat the bottom 212. The substrate 40 is fastened in the packing case 20,with the corresponding edges thereof being received in the groove unitdefined by the first and second grooves 215, 253. Thereby, the substrate40 is tightly fastened in the packing case 20. In addition, a displayarea of the substrate 40 is generally arranged in the central portion ofthe substrate 40. Thus when the substrate 40 is inserted into or takenout of the first and second grooves 215, 253, and when the packing case20 is undergoing transportation, the display area of the substrate 40does not contact the packing case 20. Accordingly, the electroniccomponents at the display area of the substrate 40 avoid being damagedby any friction that occurs between the substrate 40 and the packingcase 20.

Furthermore, the third surface 2135 of each first protrusion 213 extendsin a direction oblique toward the third side wall 218. The width of thesecond portion of the first groove 215 increases with increasingdistance away from the respective first or third side wall 216, 218.Peripheral sides of the substrate 40 around the display area of thesubstrate 40 are located at the second portions of the first grooves215. Therefore, when the substrate 40 is inserted into or taken out ofthe first grooves 215, and when the packing case 20 is undergoingtransportation, the auxiliary circuits at the peripheral sides of thesubstrate 40 avoid being damaged by any friction that occurs between thesubstrate 40 and the packing case 20.

Various modifications and alterations to the above-described embodimentsare possible. For example, the third surface 2135 may be a curvedsurface, as long as the width of the second portion of the first groove215 increases along with increasing distance away from the respectivefirst or third side wall 216, 218. In another example, each of thesecond protrusions 251 may have a wedge shape.

It is to be further understood that even though numerous characteristicsand advantages of the present embodiments have been set out in theforegoing description, together with details of the structures andfunctions of the embodiments, the disclosure is illustrative only, andchanges may be made in detail, especially in matters of shape, size, andarrangement of parts within the principles of the invention to the fullextent indicated by the broad general meaning of the terms in which theappended claims are expressed.

1. A packing case, comprising: a main body having four side walls; and aplurality of protrusions formed at inner sides of two opposite of theside walls; wherein at each of the opposite side walls, the protrusionsare separate from each other and parallel to each other, each of theprotrusions has a wedge shape and is perpendicular to the side walls,and each two adjacent protrusions define a groove therebetween; and thegroove comprises a first portion and a second portion, the first portionis adjacent to the side wall, and a width of the second portionincreases with increasing distance away from the side wall.
 2. Thepacking case as claimed in claim 1, wherein the grooves at one of thetwo opposite side walls are symmetrical with respect to the grooves atthe other of the two opposite side walls.
 3. The packing case as claimedin claim 1, wherein the main body further comprises a bottom, and thefour side walls are perpendicular to the bottom.
 4. The packing case asclaimed in claim 3, wherein the grooves are oriented perpendicular tothe bottom of the main body.
 5. The packing case as claimed in claim 3,wherein the bottom comprises a plurality of protrusions that areseparate from each other and parallel to each other, and each twoadjacent protrusions at the bottom define a groove therebetween.
 6. Thepacking case as claimed in claim 5, wherein the grooves at the bottomare aligned one-to-one with the grooves at one of the two opposite sidewalls and aligned one-to-one with the grooves at the other of the twoopposite side walls.
 7. The packing case as claimed in claim 1, whereineach of the protrusions comprises a first surface, a second surfaceparallel to the first surface, and a third surface, and the first andsecond surfaces are perpendicular to the corresponding side wall.
 8. Thepacking case as claimed in claim 7, wherein the second surface togetherwith a corresponding portion of the first surface of an adjacentprotrusion cooperatively define the first portion of the groove.
 9. Thepacking case as claimed in claim 8, wherein the third surface togetherwith another corresponding portion of the first surface of the adjacentprotrusion cooperatively define the second portion of the groove. 10.The packing case as claimed in claim 7, wherein the third surfaceextends from an end of the second surface in a direction oblique to thecorresponding side wall.
 11. The packing case as claimed in claim 7,wherein the third surface is a curved surface.
 12. The packing case asclaimed in claim 1, wherein a top of the main body comprises a raisedinner peripheral rim, and an outer peripheral ledge surrounding a bottomof the inner peripheral rim.
 13. The packing case as claimed in claim13, further comprising a cover, wherein the cover is engaged with themain body by fittingly abutting the inner peripheral rim and the outerperipheral ledge of the main body, the cover and the main body therebycooperatively defining a closed space.
 14. A packing case, comprising: amain body having four side walls; and a plurality of protrusions formedat inner sides of two opposite of the side walls of the main body;wherein at each of the opposite side walls, the protrusions are separatefrom each other and parallel to each other, each of the protrusions hasa wedge shape and is perpendicular to the side wall, and each twoadjacent protrusions define a groove therebetween; and the groovecomprises a first portion and a second portion, the first portion isadjacent to the side wall and has a uniform width, and the secondportion flares from the first portion such that a width of the secondportion adjacent to the first portion is the same as the width of thefirst portion and a width of the second portion farthest from the firstportion is greater than the width of the first portion.
 15. The packingcase as claimed in claim 14, wherein the grooves at one of the twoopposite side walls are symmetrical with respect to the grooves at theother of the two opposite side walls.
 16. The packing case as claimed inclaim 14, wherein each of the protrusions comprises a first surface, asecond surface parallel to the first surface, and a third surface, andthe first and second surfaces are perpendicular to the correspondingside wall.
 17. The packing case as claimed in claim 16, wherein thethird surface extends from an end of the second surface in a directionoblique to the corresponding side wall.
 18. The packing case as claimedin claim 18, wherein the third surface is a curved surface.
 19. Thepacking case as claimed in claim 14, wherein the main body furthercomprises a bottom, and the four side walls are perpendicular to thebottom, the bottom comprises a plurality of protrusions that areseparate from each other and parallel to each other, and each twoadjacent protrusions at the bottom define a groove therebetween.
 20. Thepacking case as claimed in claim 14, wherein the grooves at the bottomare aligned one-to-one with the grooves at one of the two opposite sidewalls and aligned one-to-one with the grooves at the other of the twoopposite side walls.